/*
 * Copyright (c) 2014, 2024, Marcus Hirt, Miroslav Wengner
 *
 * Robo4J is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Robo4J is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Robo4J. If not, see <http://www.gnu.org/licenses/>.
 */
package com.robo4j.util;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.ByteArrayOutputStream;
import java.io.InputStream;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.Spliterator;
import java.util.Spliterators;
import java.util.stream.Stream;
import java.util.stream.StreamSupport;

/**
 * Streams related utils
 *
 * @author Marcus Hirt (@hirt)
 * @author Miroslav Wengner (@miragemiko)
 */
public final class StreamUtils {
    private static final Logger LOGGER = LoggerFactory.getLogger(StreamUtils.class);
    public static final int STREAM_END = -1;

    /**
     * convert Enumeration to the Stream
     *
     * @param e        enumeration of element E
     * @param parallel parallel
     * @param <E>      element instance
     * @return stream of elements E
     */
    public static <E> Stream<E> streamOfEnumeration(Enumeration<E> e, boolean parallel) {
        return StreamSupport.stream(Spliterators.spliteratorUnknownSize(new Iterator<E>() {
            public E next() {
                return e.nextElement();
            }

            public boolean hasNext() {
                return e.hasMoreElements();
            }
        }, Spliterator.ORDERED), parallel);
    }

    /**
     * convert iterable to the stream
     *
     * @param iterable iterable of element E
     * @param parallel parallel
     * @param <E>      element instance
     * @return Stream of elements
     */
    public static <E> Stream<E> streamOf(Iterable<E> iterable, boolean parallel) {
        return StreamSupport.stream(iterable.spliterator(), parallel);
    }

    /**
     * convert stream to iterable
     *
     * @param stream stream of element E
     * @param <E>    element instance
     * @return iterable of elements E
     */
    public static <E> Iterable<E> iterableOf(Stream<E> stream) {
        return stream::iterator;
    }

    /**
     * converting input stream to byte array
     *
     * @param inputStream input stream
     * @return byte array
     */
    public static byte[] inputStreamToByteArray(InputStream inputStream) {
        try (final ByteArrayOutputStream baos = new ByteArrayOutputStream()) {
            int imageCh;
            while ((imageCh = inputStream.read()) != STREAM_END) {
                baos.write(imageCh);
            }
            inputStream.close();
            baos.flush();
            return baos.toByteArray();
        } catch (Exception e) {
            LOGGER.error(e.getMessage(), e);
            return new byte[0];
        }
    }
}
